Role of suppressor T cells in autoimmune responses induced by polyclonal B cell activators.

In order to investigate a possible role of suppressor T cells in the maintenance of self tolerance, we compared the autoimmune response induced by LPS in cultures of untreated spleen cells with the one of anti-theta treated spleen lymphocytes. It was constantly found that T cell depletion never resulted in an increase in the number of plaques directed against autologous albumin coupled SRBC. The same finding was also apparent when the autoimmune response given by spleen cells of old, normal or thymectomized and young untreated animals was compared. In order to exclude the possibility that lack of increase of the autoimmune response in animals with T cells deficiency was due to long-lived suppressor functions, cells or factors, we compared the response to autologous albumin, as induced by LPS, in spleen cells of nude mice with the one given by their normal littermates. Since even in this instance no significant increase could be detected, we conclude that suppressor cells do not play an active role in the maintenance of self tolerance.